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Water‐enabled electricity generation technologies that are highly accessible and fundamentally clean are promising for next‐generation green energy. However, the challenge of scalability in both material processing and device fabrication greatly limits their practical applications. A high‐performance polyelectrolyte moist‐electric generator (MEG), which can be directly 3D printed for massive production and efficient integration, is reported. The printed MEG (p‐MEG) generates a high open‐circuit voltage of 0.8 V and a short‐circuit‐current density of 0.12 mA cm−2 by actively harvesting moisture from humid conditions. The synergistic effects of moisture gradient, ionic concentration gradient, and ion diffusion gradient, which remarkably enhance the driving force to separate ion pairs and notably facilitate the directional ion transport, are responsible for the high power generation performance of p‐MEG, as further backed up by in situ ion dynamics investigations and molecular simulations. When connected in serial and parallel, hundreds of p‐MEGs can deliver a high voltage of more than 180 V and a current of more than 1 mA. A constructed "moisture‐powered cup lamp" that lights up for hours further demonstrates the practicability of p‐MEG. This work provides a feasible and scalable 3D printing approach for the next‐generation environment‐adaptive self‐powered system. [ABSTRACT FROM AUTHOR]

Abstract: Simultaneously integrating efficient optical gain and high charge carrier mobility in organic semiconductors for multifunctional optoelectronic applications is challenging. Here, a new thiophene/phenylene derivative, 5,5′‐bis(2,2‐diphenylvinyl)‐bithiophene (BDPV2T), containing an appropriate butterfly molecular configuration in a π‐conjugated structure, is designed to achieve both solid‐state emission and charge transport properties. The prepared BDPV2T crystals exhibit excellent light‐emitting characteristics with a photoluminescence quantum yield of 30%, low light‐amplification threshold of 8 kW cm−2, high optical net gain up to 70 cm−1, and high charge carrier mobility up to 1 cm2 V−1 s−1 in their J‐aggregate single crystals. These BDPV2T single crystal characteristics ensure their application potential for photodetectors, field‐effect transistors, and light‐emitting transistors. High optoelectronic performances are achieved with photoresponsivity of 2.0 × 103 A W−1 and light on/off ratio of 5.4 × 105 in photodetectors, and efficient ambipolar charge transport (µh: 0.14 cm2 V−1 s−1, µe: 0.02 cm2 V−1 s−1) and electroluminescence characteristics in light‐emitting transistors. The remarkably integrated optoelectronic properties of BDPV2T suggest it is a promising candidate for organic multifunctional and electrically pumped laser applications. [ABSTRACT FROM AUTHOR]

The state‐of‐the‐art power conversion efficiency (PCE) of organic solar cells (OSCs) is typically achieved in the devices fabricated by toxic halogen solvents with complex post‐treatment processes in strictly inert atmosphere. Developing suitable processing method for printing in ambient air using eco‐friendly solvents with continuous solution supply and fabricating efficient devices without any post‐treatment are intensively desired. Controlling the crystallization kinetics to fine‐tune the acceptor's assembly behavior with a second donor for favorable morphological evolution is an effective approach to achieve above requirements. Herein, a kinetics‐controlling strategy is implemented by introducing a strong crystalline small molecule, BTR‐Cl, to enhance the crystallinity of acceptors. The combined in situ spectra characterizations revealed that the earlier aggregation of acceptor and modulation in conformation of PM6 can be achieved. This unique aggregation behavior facilitated enhanced film crystallization with reduced paracrystallinity of π–π stacking, resulting in improved charge transport and inhibited charge recombination. An outstanding PCE of 17.50% is obtained for the device processed with o‐xylene via ambient air printing without any post‐treatment. More significantly, efficient all‐printed inverted devices and large‐area modules are prepared. The generalization of this strategy has been confirmed in other efficient systems, suggesting a great potential for universally fabricating high‐efficiency and eco‐friendly OSCs. [ABSTRACT FROM AUTHOR]

Excessive inflammation, bacterial infection, and blocked angiogenesis make diabetic wound healing challenging. Multifunctional wound dressings have several advantages in diabetic wound healing. In addition, the pH regulation of the microenvironment is shown to be a key factor that promotes skin regeneration through cellular immune regulation. However, few reports have focused on the development of functional dressings with the ability to regulate the pH microenvironment and promote diabetic wound healing. This study presents a novel approach for regulating the pH microenvironment of diabetic wound sites using a glycopeptide‐based hydrogel consisting of modified hyaluronic acid and poly(6‐aminocaproic acid). This hydrogel forms a network through Schiff base interactions and metal complexation, which suppresses inflammation and accelerates angiogenesis during wound healing. Hydrogels not only have adequate mechanical properties and self‐healing ability but can also support tissue adhesion. They can also promote the secretion of inducible cAMP early repressor, which promotes the polarization of macrophages toward the M2 type. The in vivo results confirm that hydrogel promotes diabetic wound repair and skin regeneration by exerting rapid anti‐inflammatory effects and promoting angiogenesis. Therefore, this hydrogel system represents an effective strategy for treating diabetic wounds. [ABSTRACT FROM AUTHOR]

The power conversion efficiency (PCE) of organic solar cells (OSCs) has reached high values of over 19%. However, most of the high‐efficiency OSCs are fabricated by spin‐coating with toxic solvents and the optimal photoactive layer thickness is limited to 100 nm, limiting practical development of OSCs. It is a great challenge to obtain ideal morphology for high‐efficiency thick‐film OSCs when using non‐halogenated solvents due to the unfavorable film formation kinetics. Herein, high‐efficiency ternary thick‐film (300 nm) OSCs with PCE of 15.4% based on PM6:BTR‐Cl:CH1007 are fabricated by hot slot‐die coating using non‐halogenated solvent (o‐xylene) in the air. Compared to PM6:BTR‐Cl:Y6 blends, the stronger pre‐aggregation of CH1007 in solution induces the earlier aggregation of CH1007 molecules and longer aggregation time, and thus results in high and balanced crystallinity of donors and acceptor in CH1007‐based ternary film, which led to high‐carrier mobility and suppressed charge recombination. The ternary strategy is further used to fabricate high‐efficiency, thick‐film, large‐area, and flexible devices processed from non‐halogenated solvents, paving the way for industrial development of OSCs. [ABSTRACT FROM AUTHOR]

Two compatible donors (PBDB‐T and PTB7‐Th) and two miscible acceptors (ITIC and FOIC) are employed to deliver a parallel‐alloy morphology model in non‐fullerene‐based quaternary organic solar cells. PBDB‐T and PTB7‐Th form a parallel link with a slight adjustment of molecular packing into enhanced face‐on crystallites while ITIC disperses into discontinuous FOIC microcrystal regions to form continuous and ordered alloy‐like acceptor phases. Characterization of blend morphology highlights the parallel‐alloy model—enabled by the introduction of PBDB‐T and ITIC, which contributes to improved molecular packing and reduced domain size resulting in efficient charge generation and consistent transport channels. This successful parallel‐alloy quaternary blend morphology demonstrates an enhanced optical absorption, optimized domain size, and nanostructures toward simultaneous improvement in charge transfer and transport. Therefore, a power conversion efficiency of 12.52% is realized for a quaternary device which is 6% higher than the ternary device (PBDB‐T:PTB7‐Th:FOIC) and 12% higher than the binary device (PTB7‐Th:FOIC). Domination of quaternary devices over ternary and binary blends, which is another feasible way to realize highly efficient devices through further investigation of quaternary OSCs, is presented.Quaternary organic solar cells based on PBDB‐T:PTB7‐Th:ITIC:FOIC are reported to deliver a parallel‐alloy morphology mode in non‐fullerene‐based devices. In the quaternary system, the parallel‐like donors and alloy‐like acceptors together facilitate transfer kinetics, optimize blend morphology, and drive the device efficiency toward over 12.5%, which indicates the great potential of quaternary organic solar cells. [ABSTRACT FROM AUTHOR]

Photodetectors, converting optical signals from specific wavelengths to electrical signals, have many applications on photoimaging, optical communication, and environmental monitoring. Solution‐processed organic photodetectors (OPDs) based on organic materials emerge promise especially for wearable electronics and smart buildings. In this work, new all‐polymer photodetectors (all‐PPDs) are developed based on bulk‐heterojunction active layers which incorporate a donor polymer and an acceptor polymer. The inverted all‐PPDs exhibit outstanding external quantum efficiency over 70%, low dark current density (Jd) of 1.1 × 10−8 A cm−2, and high detectivity (D*) over 3.0 × 1012 Jones with planar response over the entire visible range. It is one of the best‐performing all‐PPDs reported so far and is also comparable with many organic and inorganic photodetectors. By using lamination technique, large‐area, semitransparent, flexible, and "fully" polymeric photodetectors are successfully fabricated for the first time, with D* over 1011 Jones for double‐side light detection. The results highlight the great potential for producing high‐performance all‐PPDs by taking advantages of various device architecture and solution‐processing techniques. Large‐area, semitransparent, and flexible all‐polymer photodetectors are realized by incorporating a pair of donor and acceptor polymers and by using a lamination method. Both sides of these all‐polymer photodetectors respond visible light signals with nearly identical D* over 1.0 × 1011 Jones. [ABSTRACT FROM AUTHOR]